Hinge apparatus for cover of image forming apparatus

ABSTRACT

A hinge apparatus for a cover of an image forming apparatus has a hinge body with supporting brackets, movably inserted into a coupling hole positioned in a main body of the image forming apparatus, a hinge cam connected to the cover and pivotably connected to the supporting brackets, and a pressure device disposed at the hinge body to press the hinge cam. Accordingly, the hinge apparatus can be implemented with a simple and easy assembly operation, since it is not a complicated structural connection among the component parts of the hinge apparatus.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of Korean Patent ApplicationNo. 2003-27806, filed Apr. 30, 2003, in the Korean Intellectual PropertyOffice, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a hinge apparatus, and moreparticularly to a hinge apparatus that supports a cover of an imageforming apparatus, such as a photocopier, a scanner, or a multifunctionmachine, so that the cover thereof pivotably opens and closes.

[0004] 2. Description of the Related Art

[0005] An image forming apparatus, which has document scanning functionlike a photocopier, a scanner, or a multifunction machine, scans adocument, then stores a scanned image as data, or prints the image on aprinting paper. Such an image forming apparatus includes a documentglass disposed on a main body of the image forming apparatus to scan thedocument, a cover to secure the document laid on the document glass, anda hinge apparatus connecting the cover and the main body of the imageforming apparatus.

[0006]FIG. 1 shows a hinge apparatus 30 to open and close the cover ofthe conventional image forming apparatus 10, disclosed in JapanesePatent Publication No. 11305358. As shown in FIG. 1, the conventionalhinge apparatus 30 includes a hinge body 32 integrally formed with aspring pin 31, and a spring 33 connected to the spring pin 31 at oneend. A cover 20 is provided with a hinge pin 21 that is inserted into along hole 32 a positioned in the hinge body 32. The spring 33 isconnected to the hinge pin 21, and therefore, the cover 20 and the hingeapparatus 30 form a set. A cam part 20 a, which is disposed at the cover20, is in tight contact with the hinge body 32 under a recovery force ofthe spring 33. Furthermore, the hinge body 32 is disposed to move upwardand downward within a coupling hole 10 a positioned in the main body ofthe image forming apparatus 10.

[0007] The conventional image forming apparatus with the above structurehas a document glass 11, which is exposed and covered through pivotingof the cover 20 centering on the hinge pin 21. The cover 20 opens andcloses slowly, since the cover 20 is moved with the cam part 20 a of thecover 20 being in close contact with the hinge body 32. Moreover, when athick document is laid upon the document glass 11, the hinge body 32 islifted upward to a predetermined height, so that the cover 20 uniformlypresses the document, such as a thick book, laid upon the document glass11.

[0008] But in the above conventional hinge apparatus 30, there is adifficulty in assembling the cover 20 and the hinge apparatus 30, sincethe both ends of the spring 33 are directly connected with the cover 20and the hinge body 32, that are respectively at an opposite side. Inother words, the spring 33 has a high elastic modulus to secure a slowopening and closing of the cover is used, and accordingly it is not easyto connect the spring 33 with the spring pin 31 of the hinge apparatus30 and with the hinge pin 21 of the cover 20.

[0009] Also, a friction between the cam part 20 a of the cover 20 andthe hinge body 32 generates a noise in opening and closing of the cover20. Another problem is that the hinge body 32 can be released out of thecoupling hole 10 a of the main body of the image forming apparatus, whena thick document is being scanned.

SUMMARY OF THE INVENTION

[0010] The present invention has been made to solve the aforementionedproblems. Accordingly, an aspect of the present invention is to providea hinge apparatus for a cover of an image forming apparatus, which isassembled with ease and decreases a noise occurring in opening andclosing the cover.

[0011] To achieve the above and/or other aspects of the presentinvention, a hinge apparatus for a cover of the image forming apparatusis provided. The hinge apparatus opens and closes the cover of the imageforming apparatus, and pivotably connects a main body of the imageforming apparatus with the cover, to expose and cover a document glass.The hinge apparatus has: a hinge body, movably inserted in a firstdirection into a coupling hole positioned in the main body of the imageforming apparatus, and having supporting brackets; a hinge cam, of whichone side is connected to the cover, and pivotably connected to thesupporting brackets; and a pressure device disposed at the hinge body topress the hinge cam.

[0012] According to one aspect, a housing chamber is provided within thehinge body, and the pressure device has: a pusher disposed in thehousing chamber, that protrudes out of the housing chamber; and a springdisposed within the housing chamber to press the pusher.

[0013] According to one aspect, the hinge cam has a body portionconnected to the cover, and a cam part pivotably connected to the bodyin close contact with the pressure device.

[0014] According to one aspect, each of the supporting brackets and thecam part is provided with a shaft hole, and the hinge apparatusadditionally has a hinge shaft inserted through the respective shaftholes, to pivotably connect the cam part with the supporting brackets.

[0015] According to one aspect, a center of the hinge shaft is locatedtoward the document glass compared to a pressure central line of thepressure device.

[0016] According to one aspect, the pusher has a locking protrusion, thehinge body is provided with a guide slot, and the locking protrusion isinserted into the guide slot, and prevents the release of the pusherfrom the hinge body.

[0017] According to one aspect, the hinge body has, a first protrusionpositioned at one side of the hinge body, to prevent the supportingbrackets from entering the coupling hole.

[0018] According to one aspect, the main body has: a hooking portionpositioned at the lower part of the main body of the image formingapparatus; and, the hinge body has a second protrusion positioned at afirst side of the hinge body, that is caught by the hooking portion,which prevents the release of the hinge body from the coupling hole whenthe hinge body is moved in a direction opposite the first direction.

[0019] According to one aspect, at least one of the pusher and the hingecam is made of a lubricating resin.

[0020] Additional aspects and/or advantages of the invention will be setforth in part in the description which follows and, in part, will beobvious from the description, or may be learned by practice of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] These and other features, aspects, and/or advantages of thepresent invention will become apparent and more readily appreciated fromthe following description of the embodiments, taken in conjunction withthe accompanying drawings, in which:

[0022]FIG. 1 shows a cross sectional view of a conventional hingeapparatus to open and close a cover of an image forming apparatus;

[0023]FIG. 2 shows an exploded perspective view of a hinge apparatus toopen and close a cover according to an embodiment of the presentinvention;

[0024]FIG. 3 shows a view of the hinge apparatus of FIG. 2 connected tothe cover of the image forming apparatus after assembly; and

[0025]FIGS. 4 through 7 show cross sectional views, to describe anoperation of the hinge apparatus of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Reference will now be made in detail to the embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to the like elementsthroughout. The embodiments are described below to explain the presentinvention by referring to the figures.

[0027] Referring to FIGS. 2 and 3, a hinge apparatus 100 to open andclose a cover 50 of an image forming apparatus 40, according to anembodiment of the present invention, includes a hinge body 110, apressure device 120, and a hinge cam 130.

[0028] The shown embodiment of the hinge body 110 has a configuration ofa hexahedron box, of which an interior is void and one side is opened,and is received in a coupling hole 40 a positioned in a main body of theimage forming apparatus 40, to be moved upward and downward. A housingchamber 111 is provided inside of the hinge body 110, and at one side ofthe housing chamber 111, an open portion 111 a is positioned tocommunicate with an exterior. It is understood, however, that the hingebody 110 can have other configurations that the shown hexahedron box.

[0029] Furthermore, a pair of supporting brackets 113 extended fromsidewalls of the hinge body 110, and are positioned at sides of the openportion 111 a. Each of the supporting brackets 113 supports the hingecam 130 and has a shaft hole 113 a therein. At the sidewalls of thehinge body 110, guide slots 112 a are positioned to guide an upward anddownward movement of the pressure device 120.

[0030] Also, on each of a front wall 114 and a rear wall 115 of thehinge body 110, that are connected with the sidewalls, a firstprotrusion 116 is positioned to protrude outward, thereby restrictingthe inserting range of the supporting brackets 113 into the couplinghole 40 a. The first protrusions 116 are located at lower parts of thesupporting brackets 113. When the hinge body 110 is inserted into thecoupling hole 40 a, the first protrusions 116 are caught at the mainbody of the image forming apparatus 40, and therefore, the supportingbrackets 113 protrude above a document glass 41 of the main body of theimage forming apparatus 40.

[0031] Also, on a bottom wall 118 of the hinge body 110 opposite to theopen portion 111 a, a spring support 117 protrudes to support a firstend of a spring 122, which will be described later.

[0032] In addition, at a lower part of the front wall 114, a secondprotrusion 119 protrudes, and is coplanar with the bottom wall 118. Whenthe hinge body 110 is moved out of the coupling hole 40 a, since thesecond protrusion 119 is caught by a hooking portion 42 disposed at oneside of the main body of the image forming apparatus 40, as shown inFIG. 4, the release of the hinge body 110 from the coupling hole 40 a isprevented.

[0033] The pressure device 120 includes a pusher 121 and the spring 122,for a smooth pivoting of the hinge cam 130, since the pressure device120 inhibits the pivoting of the hinge cam 130 pivotably supported bythe supporting brackets 113. The pusher 121 is disposed to move downwardand upward, to protrude outward through the open portion 111 a of thehinge body 110. The pusher 121 has locking protrusions 123 on opposingsides, positioned so that the locking protrusion 123 is inserted intothe guide slots 112 a of the hinge body 110. Therefore, the pusher 121moves upward and downward within the length of the guide slots 112 a, sothat the pusher 121 is not released from the hinge body 110. The spring122, that presses the pusher 121 toward the open portion 111 a, isdisposed within the housing chamber 111. The first end of the spring 122is supported by the spring support 117 of the hinge body 110, and asecond end of the spring 122 is supported by a spring support 124 (seeFIG. 4) positioned at a lower part of the pusher 121.

[0034] In assembling the pressure device 120, after the spring 122 isdisposed in the housing chamber 111, the pusher 121 is connected to thehinge body 110. The pusher 121, which is elastically supported by thespring 121, has the locking protrusions 123, which contact upper sidesof the guide slots 112 a. Assembly is simplified if a length of thespring 122 is substantially the same as a height from a bottom of thepusher 121 to the bottom wall 118 when the locking protrusions 123contact the upper sides of the guide slots 112 a. In this case, as thepusher 121 is pushed into the housing chamber 111 to insert the lockingprotrusions 123 into the guide slots 112 a, a strain of the spring 122does not occur. Accordingly, the user does not need to induce a strainpressure on the spring 122, which according to one aspect, has a highelastic stiffness. While described in terms of a spring 122, it isunderstood that other mechanisms can be used to bias the pusher 121,such as combinations of springs, hydraulic or pneumatic mechanisms,elastic materials, of other such devices.

[0035] In addition, according to one aspect, the pusher 121 is made of alubricating resin, since there is a friction inherent in the slidingmovement of the hinge cam 130. So-called “engineering plastics” can beused as the lubricating resin, such as polyethylene, polybutyleneterephthalate, and polyamide.

[0036] The hinge cam 130 includes a body portion 131 connected to thecover 50 of the image forming apparatus, and a cam part 132 to slide inclose contact with the pusher 121, under a predetermined pressure. Thebody portion 131 has a screw hole 131 a, and is combined with the cover50 by inserting a fastening member, like a screw 60, into a boss portion52 (see FIG. 4), through the screw hole 131 a, with one side of the bodyportion 131 being supported by a locking projection 51 (see FIG. 4) inthe cover 50.

[0037] The cam part 132 is integrally combined to the body portion 131,and has a shaft hole 132 a. To put the hinge cam 131 in a conditionready to pivot on a hinge shaft 140, the cam part 132 is positioned insuch a manner that the shaft hole 132 a of the cam part 132 is alignedwith the shaft holes 113 a of the supporting brackets 113, and then thehinge shaft 140 is inserted into each shaft hole 113 a, 132 a.

[0038] A groove portion 140 a is positioned at one end of the hingeshaft 140. When the hinge shaft 140 is inserted into and passed throughthe shaft hole 132 a of the cam part 132 and the shaft holes 113 a ofthe supporting brackets 113, a coupling ring 141 is fixed to the grooveportion 140 a. As a result, the hinge shaft 140 is prevented fromreleasing out of each shaft hole 113 a, 132 a.

[0039] As shown in FIG. 5, according to one aspect, a center C of thehinge shaft 140 is located at a predetermined interval toward adirection of the document glass 41 from a pressure central line L of thehinge cam 130 and the pusher 121. As a result, the pivot of the hingecam 130 is more efficiently inhibited. According to one aspect, thisallows, the spring 122 employed to be inexpensive, and have a lowelastic modulus. In addition, according to one aspect, since there isfriction inherent in the sliding movement of the pusher 121, the hingecam 130 is made with a lubricating resin, such as polyethylene,polybutylene terephthalate, and polyamide.

[0040] Meanwhile, although the above embodiment of the present inventionemploys the hinge shaft 140 as a way to combine the hinge cam 130 to thehinge body 110, the present invention is not limited to this embodiment.Therefore, the hinge cam 130 can be pivotably connected to the hingebody 110 through various ways. For example, according to one aspect,although not shown in the drawings, protrusions are positioned at sidesof the cam part 132 in the hinge cam 130, and the protrusions areinserted into the shaft holes 113 a of the supporting brackets 113.

[0041] Hereinafter, referring to the attached drawings, an operation ofthe hinge apparatus 100 according to an embodiment of the presentinvention is described in detail.

[0042] To insert the hinge apparatus 100 connected with the cover 50into the coupling hole 40 a in the main body of the image formingapparatus 40, as shown in FIG. 4, the hinge body 110 is first tilted sothat the second protrusion 119 can be inserted into the coupling hole 40a in the main body of the image forming apparatus 40. Then, after movingthe hinge body 110 to an upright position along a direction of arrow A,and inserting an end of the rear wall 115 of the hinge body 110 into thecoupling hole 40 a, the hinge body 110 is pushed into the coupling hole40 a. As the first protrusion 116 of the hinge body 110 contacts anupper side of the main body of the image forming apparatus 40, the cover50 and the main body of the image forming apparatus 40 are coupled bythe hinge apparatus 100. The cover 50 can secure a thin document such asa sheet of paper in tight contact with the document glass 41, as shownin FIG. 5.

[0043] In addition, to open the cover 50 and expose the document glass41, as shown in FIG. 6, the cover 50 is pivoted and pushed overcompletely in a clockwise direction, and then the hinge cam 130 and thepusher 121 contact under the least pressure, since the spring is in aleast compressed state. Then, if a document is positioned on thedocument glass 41 and the cover 50 is pivoted in a counterclockwisedirection, the pivoting of the hinge cam 130 is inhibited, as thepressure between the hinge cam 130 and the pusher 121 increasescontinuously. As a result, the cover 50 closes slowly.

[0044] In the mean time, if a thick document, like a book, is positionedon the document glass 41, as shown in FIG. 7, the hinge body 110 ismoved upward to an upper side of the coupling hole 40 a, to expand aspace between the cover 50 in the closed position and the document glass41. In a process of moving the hinge body 110 to the upper side of thecoupling hole 40 a, the second protrusion 119 of the hinge body 110 iscaught by the hooking portion 42 on the main body of the image formingapparatus 40. Consequently, the hinge body 110 is not released out ofthe coupling hole 40 a.

[0045] According to the embodiment of the present invention describedabove, there is an advantage that the hinge apparatus 100 can beimplemented with a simple and easy assembly operation, since it is not acomplicated structural connection among the component parts that composethe hinge apparatus 100.

[0046] Also, the hinge apparatus 100 can efficiently improve theusability of the image forming apparatus, since the hinge apparatus 100decreases noise occurring when opening and closing the cover 50, andprevents the cover 50 from unintentionally closing.

[0047] While described as being used in an image forming apparatus, itis understood that the hinge apparatus 100 would be useful in otherdevices beyond image forming apparatuses, such as presses that compressvarious size items, cooking apparatuses, etc.

[0048] Although a few embodiments of the present invention have beenshown and described, it would be appreciated by those skilled in the artthat changes may be made in this embodiment without departing from theprinciples and spirit of the invention, the scope of which is defined inthe claims and their equivalents.

What is claimed is:
 1. A hinge apparatus to open and close a cover of animage forming apparatus, which pivotably connects the cover to a mainbody of the image forming apparatus, to expose and cover a documentglass, the hinge apparatus comprising: a hinge body movably inserted ina first direction into a coupling hole positioned in the main body ofthe image forming apparatus, and having supporting brackets; a hingecam, connected to the cover, and pivotably connected to the supportingbrackets; and a pressure device disposed at the hinge body to press thehinge cam.
 2. The hinge apparatus of claim 1, wherein: the hinge body isprovided with a housing chamber; and the pressure device comprises apusher disposed in the housing chamber, that protrudes from the housingchamber, and a spring disposed within the housing chamber to press thepusher.
 3. The hinge apparatus of claim 1, wherein the hinge camcomprises: a body portion connected to the cover; and a cam part thatpivots in close contact with the pressure device.
 4. The hinge apparatusof claim 3, wherein: the cam part and each of the supporting bracketsare provided with a shaft hole, respectively, and the hinge apparatusfurther comprises a hinge shaft inserted through the respective shaftholes, to pivotably connect the cam part to the supporting brackets. 5.The hinge apparatus of claim 4, wherein: a center of the hinge shaft islocated toward the document glass compared to a pressure central line ofthe pressure device.
 6. The hinge apparatus of claim 2, wherein: thepusher comprises a locking protrusion; the hinge body is provided with aguide slot; and the locking protrusion is inserted into the guide slot,and prevents the release of the pusher from the hinge body.
 7. The hingeapparatus of claim 1, wherein the hinge body comprises: a firstprotrusion positioned at one side of the hinge body, to prevent thesupporting brackets from entering the coupling hole.
 8. The hingeapparatus of claim 1, wherein: the main body comprises a hooking portionpositioned at one side of the main body of an image forming apparatus;and the hinge body comprises a second protrusion positioned at a firstside of the hinge body, that is caught by the hooking portion, therebypreventing the release of the hinge body from the coupling hole when thehinge body is moved in a direction opposite the first direction.
 9. Thehinge apparatus of claim 2, wherein: the pusher is made of a lubricatingresin.
 10. The hinge apparatus of claim 1, wherein: the hinge cam ismade of a lubricating resin.
 11. A hinge apparatus rotatably connectinga cover and a main body, the hinge apparatus comprising: a hinge body,with a void therein and a supporting bracket, movable in an opening inthe main body; a pressure device, movable within the void, and biasedtoward a first end of the hinge body; and a hinge cam, connected to thecover, rotatably connected to the supporting bracket, and slidablyengaging the pressure device.
 12. The hinge apparatus according to claim11, wherein: the hinge cam and the supporting bracket each have a shafthole; and the hinge apparatus further comprises a hinge shaft insertedthrough the shaft holes of the hinge cam and the supporting bracket, torotatably connect the hinge cam and the supporting bracket.
 13. Thehinge apparatus according to claim 12, wherein: the hinge shaft isprovided with at least one groove portion; and the hinge apparatusfurther comprises at least one coupling ring, fixed to the at least onegroove portion, to maintain a position of the hinge shaft with respectto the shaft holes of the hinge cam and the supporting bracket.
 14. Thehinge apparatus according to claim 11, wherein: a protrusion is providedon one of the hinge cam and the supporting bracket; and a receiving partreceiving the protrusion is provided on the remaining one of the hingecam and the supporting bracket, to rotatably connect the hinge cam andthe supporting bracket.
 15. The hinge apparatus according to claim 11,wherein: the hinge body comprises a first protrusion, to limit an amountthe hinge body moves into the opening in the main body.
 16. The hingeapparatus according to claim 15, wherein: the opening in the main bodyis provided with a hooking portion; and the hinge body comprises asecond protrusion, to limit an amount the hinge body moves out of theopening in the main body.
 17. The hinge apparatus according to claim 11,wherein: the pressure device comprises a pusher and a biasing elementthat biases the pusher toward the first end of the hinge body; and thehinge body comprises a biasing element support, wherein a first end ofthe biasing element engages a first end of the pusher, and a second endof the biasing element engages the biasing element support.
 18. Thehinge apparatus according to claim 17, wherein the pusher comprises alocking protrusion; and the hinge body comprises a wall with a guideslot, wherein the locking protrusion is inserted into the guide slot, toguide and limit movement of the pusher within the void of the hingebody.
 19. The hinge apparatus according to claim 18, wherein: a locationof the guide slot is defined to prevent the pusher from being releasedfrom the hinge body.
 20. The hinge apparatus according to claim 18,wherein: the biasing element comprises a spring; and a length of thespring is defined as approximately a distance between the first end ofthe pusher and the spring support, when the locking protrusion of thepusher contacts a side of the slot nearest the first end of the hingebody.
 21. The hinge apparatus according to claim 17, wherein: at leastone of the pusher and the hinge cam are made of a lubricating resin. 22.The hinge apparatus according to claim 11, wherein the hinge camcomprises: a body portion connected to the cover; and a cam partslidably engaging the pressure device.
 23. The hinge apparatus accordingto claim 22, wherein: the body portion and the cam part are integrallyformed.
 24. The hinge apparatus according to claim 12, wherein: a centerof rotation of the hinge shaft is offset by a predetermined distancefrom a line along which a center of the pressure device moves, toinhibit rotation of the hinge cam.
 25. An apparatus having a cover and amain body connected by the hinge apparatus of claim
 11. 26. A hingeapparatus, rotatably connecting a cover and a main body, the hingeapparatus comprising: a hinge body with a supporting bracket, moveablyinserted into a cavity in the main body; a hinge cam connected to thecover and pivotably connected to the supporting bracket; and a pressuredevice, disposed at the hinge body to press the hinge cam and inhibitrotation of the hinge cam.